1
2
3
4
5
6
A
B
C
D
6
5
4
3
2
1
D
C
B
A
Title
Number
Revision
Size
B
Date:
24-May-2009
Sheet of
File:
C:\PROJEC~2\..\89S_EVB.SCH
Drawn By:
[AA-01] 89SXX Project Board
+ E1
10U
R1
10K
X1
11.05M
VCC
GND
4
VCC
8
A1
2
A2
3
WP
7
SCL
6
SDA
5
A0
1
U2
AT24CXX
VCC
SCL
SDA
C?
100N
VCC
1
2
3
4
5
6
J?
ISP
VCC
P1.5
P1.6
P1.7
RST
RST
+ E?
470U
C?
100N
+ E?
470U
1
2
J?
CON2
INPUT 9-12VDC
EEPROM MEMORY
MAIN PROCESSOR
RXD
TXD
STR
ISP PROGRAMMING
R?
1K
R?
120
R?
1K
VCC
VCC
RXD
TXD
DIR
DE
3
RE
2
D
4
A
6
B
7
R
1
VCC
8
GND
5
U?
DS75176B
1
2
3
4
J?
CON4
RS485 XCEIVER
C?
33P
C?
33P
SDA
SCL
2
3
4
5
6
7
8
9
1
RP?
10K
VCC
R2IN
8
T1IN
11
T2OUT
7
R1IN
13
T2IN
10
R1OUT
12
R2OUT
9
T1OUT
14
C1+
1
C1-
3
C2+
4
C2-
5
V-
6
V+
2
VCC
16
GND
15
U?
MAX232
+
E?
1U
+
E?
1U
VCC
+
E?
1U
+
E?
1U
VCC
1
6
2
7
3
8
4
9
5
K?
DB9
RXD
TXD
AUX2
AUX1
SW?
SW-PB
R?
100
P27
GND
4
VCC1
8
X1
2
X2
3
SCLK
7
I/O
6
RST
5
VCC2
1
U?
DS1302
X1
32K768
VCC
SCL
SDA
BAT?
3V
LD?
LED
R?
1K
VCC
REAL TIME CLOCK
DISP/KEY
EA/VP
31
X1
19
X2
18
RESET
9
RD
17
WR
16
INT0
12
INT1
13
T0
14
T1
15
P10
1
P11
2
P12
3
P13
4
P14
5
P15
6
P16
7
P17
8
P00
39
P01
38
P02
37
P03
36
P04
35
P05
34
P06
33
P07
32
P20
21
P21
22
P22
23
P23
24
P24
25
P25
26
P26
27
P27
28
PSEN
29
ALE/P
30
TXD
11
RXD
10
VCC
40
GND
20
U?
AT89SXX
D0
D1
D2
D3
RS
ENLCD
BACKLIT
KEYEN
DIR/RTC
DB?
1A
Vin
1
GND
2
+5V
3
U?
LM7805CT
C?
100N
VCC
VCC
R7
100
Q3
NPN
VSS
1
VDD
2
VO
3
RS
4
R/W
5
E
6
DB0
7
DB1
8
DB2
9
DB3
10
DB4
11
DB5
12
DB6
13
DB7
14
A
15
K
16
LCD?
LCD ALPHA
D0
D1
D2
D3
VCC
VCC
VO
VO
LCD CONTRAST
RS
ENLCD
R7
10K
BACKLIT
U?
POT2
DISP/KEY
1
2
3
4
5
6
7
8
9
10
JP?
PORT0
P00
P01
P02
P03
P04
P05
P06
P07
P20
P21
P22
P23
P24
P25
P26
DEBUG LED
P00
P01
P02
P03
P04
P05
P06
P07
P00
P01
P02
P03
P04
P05
P06
P07
1
2
3
4
5
6
7
8
9
10
JP?
PORT2
P27
P20
P21
P22
P23
P24
P25
P26
VCC
VCC
D?
4148
D?
4148
D?
4148
D?
4148
SW?
KEY1
SW?
KEY2
SW?
KEY3
SW?
KEY4
KEYEN
D0
D1
D2
D3
U?
PC817
U?
PC817
R7
10K
R7
10K
1
2
J?
CON2
1
2
J?
CON2
P00
P01
STR
1
D
2
CLK
3
OE
15
Q1
4
Q2
5
Q3
6
Q4
7
Q5
14
Q6
13
Q7
12
Q8
11
QS
9
QS
10
VCC
16
GND
8
U?
CD4094
VCC
VCC
STR
SDA
SCL
LED ARRAY INDICATOR
BARGRAPH
RS232
R7
10K
Q3
NPN
J?
RELAY-DPDT
D?
4148
VCC
1
2
3
4
J?
CON4
R?
100
R?
100
RTC
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
SW?
SW DIP-8
P00
P01
P02
P03
P04
P05
P06
P07
OPTO INPUT
LD?
LED
LD?
LED
VCC
VCC
